APC Smart-UPS: remote power shutoff?

Solution 1:

Depending on the precise model of UPS, your best bet is to wire the EPO port on the back of those UPSes to the EPO switch on the fire panel.

Smart-UPS 2200 manual, see page 6.

Since these UPSes actually have an actual Emergency Power Off function built in, in order to make your fire-inspectors happy you need to wire those ports to the EPO function of the fire-panel itself. I'm not an electrician, so I don't know the specifics of how you'd wire 10's of these to a single EPO port on the fire panel, but that's a question for your fire panel system vendor.

Half-assing it with suicide software monitors on servers connected to each UPS is the kind of close-enough that gets fire-inspectors to shake their head in that special way that means you'll have to do it all over again, but right this time.

Solution 2:

Note that there is a difference between "shut down" and "unpowered" when it comes to computers. When a server shuts itself off, the board remains powered and the server is fully capable of turning itself back on again (think of wake-on-lan). The only way to un-power an ATX-supplied board is to cut the power at (or to) the power supply. In a fire-surpression case, you want all power removed from the server, not just have the server shut itself off.

That said, if you have any advanced notice at all, the command you should send to the server isn't "gracefully shut down" -- that can take minutes to complete. Instead, your goal should be limited to protecting data integrity. An emergency sync and unmount of all filesystems is a much better option in that it usually takes less than a second to complete, which could be all the time you have.

echo s >| /proc/sysrq-trigger
echo u >| /proc/sysrq-trigger

Solution 3:

I for one would never sleep soundly knowing that a Nagios / SNMP solution was doing the job of fire supression.

The only choices I would be comfortable with are: something inside the UPS itself triggers a shutdown when it detects overheating (e.g. ambient temperature significantly above normal); or hard wiring to the EPO port (sometimes called REPO port) with some sort of thermal relay or similar. You want this to work, without the slightest shadow of doubt, under all situations.